In 15-18, use the properties of exponents to write an equivalent expression for each given expression.

What is the area of the trapezoid shown ?

In a graph with several intervals o data how does a constant interval appear? what type of scenario produces a constant interval?

How many quarts of a 50% solution of acid must be added to 20 quarts of a 20% solution of acid in order to get a 40% solution of acid?